U.S. patent number 9,602,788 [Application Number 14/746,928] was granted by the patent office on 2017-03-21 for projection device management system.
This patent grant is currently assigned to CJ CGV CO., LTD.. The grantee listed for this patent is CJ CGV CO., LTD.. Invention is credited to Su Ryeon Kang, Hwan Chul Kim.
United States Patent |
9,602,788 |
Kim , et al. |
March 21, 2017 |
Projection device management system
Abstract
A projection device management system includes two or more
projection devices which project images on a projection surface;
and a management device which corrects the image projected by each
projection device based on information on each projection device
and manages information for maintenance of each projection device,
the two or more projection devices being installed in the same
theater.
Inventors: |
Kim; Hwan Chul (Seoul,
KR), Kang; Su Ryeon (Goyang-si, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
CJ CGV CO., LTD. |
Seoul |
N/A |
KR |
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Assignee: |
CJ CGV CO., LTD. (Seoul,
KR)
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Family
ID: |
48782237 |
Appl.
No.: |
14/746,928 |
Filed: |
June 23, 2015 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20150296191 A1 |
Oct 15, 2015 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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13934983 |
Jul 3, 2013 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G03B
21/206 (20130101); H04N 9/3182 (20130101); H04N
9/3194 (20130101); G03B 21/16 (20130101); H04N
9/3147 (20130101); H04N 9/3155 (20130101); E04H
3/22 (20130101); G03B 21/14 (20130101); H04N
9/3188 (20130101); H04N 9/3144 (20130101); G03B
37/04 (20130101); G03B 21/56 (20130101); G03B
21/26 (20130101) |
Current International
Class: |
G03B
21/26 (20060101); G03B 21/14 (20060101); H04N
9/31 (20060101); G03B 21/16 (20060101); G03B
21/20 (20060101); E04H 3/22 (20060101); G03B
21/56 (20060101); G03B 37/04 (20060101) |
Field of
Search: |
;353/94,85 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Dowling; William C
Assistant Examiner: Howard; Ryan
Attorney, Agent or Firm: LRK Patent Law Firm
Parent Case Text
CROSS-REFERENCE TO RELATED PATENT APPLICATION
This application is a continuation of application Ser. No.
13/934,983, filed Jul. 3, 2013, which claims the benefit of Korean
Patent Application Nos. 10-2012-0076100, filed on Jul. 12, 2012,
and 10-2012-0130111, filed on Nov. 16, 2012, in the Korean
Intellectual Property Office, the disclosure of which is
incorporated herein in its entirety by reference.
Claims
What is claimed is:
1. A projection device management system comprising: two or more
projection devices which project images on a plurality of
projection surfaces, creating a unified image on the entire
plurality of projection surfaces; and a management device which
corrects the image projected by the projection device based on
analyzed differences in shape, material, color, reflectivity or
brightness of the plurality of projection surfaces on which the two
or more projection devices create a unified image, and manages
information for maintenance of each projection device, the
information for maintenance including operation time information of
a lamp or a cooling fan installed in the projection device,
brightness information of the lamp, information on difference in
brightness between lamps installed in the two or more projection
devices, position information of the projection device, or
temperature or humidity information of the projection device,
wherein the two or more projection devices are installed in the
same theater, wherein the plurality of projection surfaces are
arranged so as not to be parallel to each other, and to surround an
auditorium in the theater, and wherein the plurality of projection
surfaces comprise different types of projection surfaces.
2. The projection device management system of claim 1, wherein the
two or more projection devices project images which are
synchronized with each other.
3. The projection device management system of claim 2, wherein the
management device additionally corrects the image projected by each
projection device based on a difference in performance between the
two or more projection devices.
4. The projection device management system of claim 3, wherein the
management device corrects the image to be projected by each
projection device based on a difference in brightness, difference
in contrast or difference in resolution between the two or more
projection devices.
5. The projection device management system of claim 1, wherein the
management device corrects the image to be projected by each
projection device based on the properties of the plurality of
projection surfaces and controls the two or more projection devices
to project images of the same brightness.
6. The projection device management system of claim 5, wherein each
projection device includes a lamp and the management device
controls the operation of the lamps included in the two or more
projection devices and equally maintains the brightness of the
lamps.
7. The projection device management system of claim 1, wherein the
information for maintenance includes operation time information of
a lamp or cooling fan installed in each projection device.
8. The projection device management system of claim 7, wherein a
current detection device is provided in the lamp or cooling fan and
the management device obtains the operation time information of the
lamp or cooling fan based on information collected by the current
detection device.
9. The projection device management system of claim 7, wherein the
management device generates replacement guide information if the
operation time of the lamp or cooling fan is greater than a
reference value and the replacement guide information includes
identification information of the projection device which needs to
replace the lamp.
10. The projection device management system of claim 1, wherein the
information for maintenance includes brightness information of the
lamp installed in each projection device.
11. The projection device management system of claim 10, wherein
the management device generates replacement guide information if
the brightness of the lamp is less than a reference value or if the
brightness of the lamp is not maintained constant over time and the
replacement guide information includes identification information
of the projection device which needs to replace the lamp.
12. The projection device management system of claim 1, wherein the
information for maintenance includes position information of each
projection device.
13. The projection device management system of claim 12, wherein a
position detection device is provided in each projection device and
the management device obtains the position information of each
projection device based on information collected by the position
detection device.
14. The projection device management system of claim 13, wherein
the management device generates, if the position of a specific
projection device is changed, information for informing the
corresponding event, and the information includes identification
information of the projection device whose position is changed.
15. The projection device management system of claim 1, wherein
each projection device detects internal temperature or humidity
and, if the temperature or humidity of a specific projection device
is greater than a reference value, the management device stops the
operation of the corresponding projection device.
16. The projection device management system of claim 1, wherein the
management device comprises: an image correction unit which
corrects the image projected by each projection device based on
analyzed differences in shape, material, color, reflectivity or
brightness of the plurality of projection surfaces on which the two
or more projection devices create a unified image; and a
maintenance management unit which generally manages the information
for maintenance of each projection device.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a projection device management
system and, more particularly, to a projection device management
system which can correct images projected by two or more projection
devices installed in a theater, control the operation of the two or
more projection devices, and further manage maintenance information
on the two or more projection devices.
2. Description of the Related Art
Conventionally, in order to reproduce images such as movies,
advertisements etc., two-dimensional images are projected on a
single screen arranged in front of a theater. However, audiences
can only watch two-dimensional (2D) images under such a system.
Three-dimensional (3D) image technologies for providing audiences
with 3D images have recently been developed. 3D image technologies
use the principle of allowing an audience to feel the 3D effect
even from a flat image when different images are presented to the
left and right eyes of the audience and combined in the brain. In
detail, two cameras equipped with different polarizing filters are
used during filming, and glasses equipped with polarizing filters
are worn by the audience such that different images are presented
to the left and right eyes during watching.
However, these 3D technologies can provide audiences with 3D
images, but the audiences just watch the images reproduced on a
single screen, which may reduce the involvement in the images.
Moreover, the direction of the 3D effect that the audiences feel is
limited to the direction of the single screen.
Furthermore, according to the conventional 3D technologies, the
audiences must wear glasses equipped with polarizing filters during
watching, which may make the audiences feel inconvenient, and
different images are artificially presented to the left and right
eyes, which may make some sensitive audiences feel dizzy or
nausea.
Therefore, a so-called "multi-projection system" which can solve
the problems of the conventional projection systems based on a
single screen has been proposed. The "multi-projection system"
refers to a technology in which a plurality of projection surfaces
are arranged around an auditorium such that synchronized images are
reproduced on the plurality of projection surfaces, thus providing
audiences with the 3D effect and involvement.
Meanwhile, two or more projection devices for projection images on
the plurality of projection surfaces are required to implement the
"multi-projection system". However, the conventional projection
systems are to simply use a single projection device, and thus when
two or more projection devices are installed in the theater, they
cannot integratedly manage and operate them.
Therefore, there is a need to develop a new system which can
integratedly manage and maintain two or more projection devices
installed in the theater.
SUMMARY OF THE INVENTION
The present invention has been made in an effort to solve the
above-described problems associated with prior art, and an object
of the present invention is to provide a projection device
management system which can correct images projected by two or more
projection devices installed in a theater and manage maintenance
information on the two or more projection devices.
To achieve the above object, a projection device management system
in accordance with an embodiment of the present invention may
comprise: two or more projection devices which project images on a
projection surface; and a management device which corrects the
image projected by each projection device based on information on
each projection device and manages information for maintenance of
each projection device, the two or more projection devices being
installed in the same theater.
Here, the two or more projection devices may project images on a
plurality of projection surfaces arranged so as not to be parallel
to each other.
The two or more projection devices may project images which are
synchronized with each other.
The management device may correct the image projected by each
projection device based on a difference in performance between the
two or more projection devices.
The management device may correct the image to be projected by each
projection device based on a difference in brightness, difference
in contrast, difference in resolution, or difference in physical
position between the two or more projection devices.
The management device may correct the image to be projected by each
projection device based also on information on the plurality of
projection surfaces.
The management device may correct the image to be projected by each
projection device based on the properties of the plurality of
projection surfaces and control the two or more projection devices
to project images of the same brightness.
Each projection device may include a lamp and the management device
may control the operation of the lamps included in the two or more
projection devices and equally maintains the brightness of the
lamps.
The information for maintenance may include operation time
information of a lamp or cooling fan installed in each projection
device.
A current detection device may be provided in the lamp or cooling
fan and the management device may obtain the operation time
information of the lamp or cooling fan based on information
collected by the current detection device.
The management device may generate replacement guide information if
the operation time of the fan or cooling fan is greater than a
reference value and the replacement guide information may include
identification information of the projection device which needs to
replace the lamp.
The information for maintenance may include brightness information
of the lamp installed in each projection device.
The management device may generate replacement guide information if
the brightness of the lamp is less than a reference value or if the
brightness of the lamp is not maintained constant over time and the
replacement guide information may include identification
information of the projection device which needs to replace the
lamp.
The management device may generate replacement guide information if
the difference in brightness between the lamps included in the two
or more projection devices is greater than a reference value and
the replacement guide information may include identification
information of the projection device which needs to replace the
lamp.
The information for maintenance may include position information of
each projection device.
A position detection device may be provided in each projection
device and the management device may obtain the position
information of each projection device based on information
collected by the position detection device.
The management device may generate, if the position of a specific
projection device is changed, information for informing the
corresponding event, and the information may include identification
information of the projection device whose position is changed.
Each projection device may detect internal temperature or humidity
and, if the temperature or humidity of a specific projection device
is greater than a reference value, the management device may stop
the operation of the corresponding projection device.
The management device may comprise: an image correction unit which
corrects the image projected by each projection device based on the
information on each projection device; and a maintenance management
unit which generally manages the information for maintenance of
each projection device.
The projection device may comprise: a current detection unit which
detects the current flowing in a lamp or cooling fan; a brightness
detection unit which detects the brightness of the lamp; a position
detection unit which detects the position of the projection device;
a temperature detection unit which detects the temperature of the
inside of the projection device; and a humidity detection unit
which detects the humidity of the inside of the projection
device.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the present
invention will become more apparent by describing in detail
exemplary embodiments thereof with reference to the attached
drawings in which:
FIGS. 1 and 2 are diagrams showing the configuration of a
projection device management system in accordance with an
embodiment of the present invention;
FIGS. 3 to 5 are diagrams showing examples of a plurality of
projection surfaces;
FIG. 6 is a diagram showing the operation of a projection device
management system in accordance with an embodiment of the present
invention;
FIG. 7 is a diagram showing the configuration of a management
device included in a projection device management system in
accordance with an embodiment of the present invention; and
FIG. 8 is a diagram showing the configuration of a projection
device included in a projection device management system in
accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a projection device management system in accordance
with embodiments of the present invention will be described in
detail with reference to the accompanying drawings. The following
embodiments are provided only for illustrative purposes so that
those skilled in the art can fully understand the spirit of the
present invention, but the present invention is not limited
thereby. Moreover, it is to be understood that all matters herein
set forth in the accompanying drawings are to be interpreted as
illustrative and may be in different forms from those actually
implemented.
Meanwhile, the term "comprising" specific components is an
"open-ended term" that simply means that the corresponding
components are present and should not be understood to exclude
other additional components.
A projection device management system in accordance with an
embodiment of the present invention will be described with
reference to FIGS. 1 to 5 below.
Referring to FIGS. 1 and 2, a projection device management system
in accordance with an embodiment of the present invention may
comprise two or more projection devices 200 which project images on
a projection surface and a management device 100 which corrects the
image projected by each projection device based on information on
each projection device and manages maintenance information on each
projection device. The two or more projection devices may
preferably be installed in the same theater.
Meanwhile, the above-mentioned "information on each projection
device" refers to information related to each projection device and
may comprise a variety of information related to the projection
device such as performance information (e.g., the brightness,
contrast, resolution, etc.) of each projection device, property
information (e.g., the brightness, material, color, reflectivity,
shape, installed structure, etc.) of the projection surface on
which each projection device projects an image, etc.
The two or more projection devices 200 refer to devices that
project images on the projection surface. These projection devices
200 may have a heating unit such as an optical system, may project
enlarged images on the projection surface, and may be implemented
in various ways. For example, the projection devices 200 may be
implemented by using a cathode ray tube (CRT), using a liquid
crystal display (LCD), by digital light processing (DLP) using a
digital micromirror device (DMD), etc.
Furthermore, the two or more projection devices 200 may be
electrically connected to the management device 100 and
integratedly controlled by the management device 100. In this case,
the two or more projection devices 200 may be connected in parallel
to the management device 100 such that both an integrated control
and an individual control are possible. Accordingly, the two or
more projection devices 200 may be integratedly or individually
controlled by the management device 100 to project images under
these controls. Meanwhile, the projection devices 200 and the
management device 100 may be connected to each other in various
ways as well as through a wired or wireless communication
network.
In addition, the two or more projection devices 200 may be
implemented as devices with different performances. For example,
the two or more projection devices 200 may be implemented as
devices with differences in performance such as a difference in
contrast between each other, difference in resolution, difference
in performance due to a difference in physical position, difference
in brightness (ANSI Lumens), etc. The differences in performance
may occur depending on the types (models) of the projection devices
200 installed in the theater, may occur due to a difference in use
time or internal parts, or may occur due to a difference in
installation environment. Meanwhile, the differences in performance
between the two or more projection devices 200 may be integratedly
controlled by the management device 100. For example, the
management device 100 may database information on the differences
in performance between the projection devices 200 and store and
manage the information in a database.
Additionally, the two or more projection devices 200 may receive
images to project from the management device 100. Here, it is
preferable that the image received by each projection device 200 is
an image corrected by the management device 100, and the image
correction by the management device 100 may preferably be performed
for each image of each projection device 200 based on individual
information of each projection device 200. Moreover, the image
correction by the management device 100 may be performed based on
the information on the differences in performance between the two
or more projection devices 200 so as to reduce the heterogeneity of
the images which may occur due to the differences in
performance.
Moreover, each projection device 200 may detect an individual
operation (on) of a lamp or cooling fan installed therein and
transmit the detected information to the management device 100. In
detail, the projection device 200 may determine whether the lamp or
cooling fan operates (on) by detecting the current flowing in the
lamp or cooling fan and transmit the detected, information together
with its identification information to the management device 100.
As a result, the management device 100 can manage cumulative
operation time information of the lamp or cooling fan installed in
each projection device 200. Meanwhile, the projection device 200
may monitor operation time information of the lamp or cooling fan
installed therein and, if the operation time information is greater
than a predetermined reference time, determine that replacement
time comes and autonomously issue a warning.
Furthermore, the projection device 200 may detect the brightness of
the lamp installed therein and transmit the detected information
together with its identification information to the management
device 100. In detail, the projection device 200 may include a
sensor device for detecting the brightness of the lamp to collect
brightness information of the lamp by means of the sensor device
and transmit the collected information to the management device
100. Meanwhile, it is preferable that the sensor device collects
the brightness information over time and transmits the collected
information to the management device 100. Moreover, the projection
device 200 may monitor the detected information (brightness
information) of the sensor device included therein and, if the
brightness information is less than a reference value or is
unstably changed, determine that the lamp has a failure and
autonomously issue a warning.
In addition, the projection device 200 may collect temperature or
humidity information of the inside of the device and transmit the
collected information together with its identification information
to the management device 100. In this case, the projection device
200 may comprise a temperature sensor or humidity sensor therein to
collect the temperature or humidity information by means of the
temperature sensor or humidity sensor and transmit the collected
information to the management device 100. Meanwhile, the projection
device 200 may autonomously monitor the temperature or humidity
therein and, if the temperature or humidity is outside a
predetermined range, determine that there is a failure and
autonomously issue a warning.
Additionally, the projection device 200 may detect its position and
transmit the detected position information to the management device
100. In detail, the projection device 200 may include a position
detection sensor (e.g., a 3-axis acceleration sensor, 3-axis gyro
sensor, etc.) which detects its position and transmit the detected
position information together with its identification information
to the management device 100. As a result, the management device
100 can manage the position information of the respective
projection devices 200 and identify an unexpected change in
position of a specific projection device. Meanwhile, the projection
device 200 may monitor information detected by the position sensor
installed therein and, if the position is unexpectedly changed,
autonomously issue a warning.
The management device 100, which is a device that generally manages
the two or more projection devices 200, generally controls the two
or more projection devices 200 and manages a variety of information
related to the two or more projection devices 200. The management
device 100 may be implemented with various electronic devices and
may be implemented in a single electronic device or in such a
manner that several electronic devices are interconnected. For
example, the management device 100 may be implemented in a single
server or in such a manner that two or more servers are
interconnected. Moreover, the management device 100 may be
implemented in such a manner that a server and other electronic
devices are interconnected or implemented in arithmetic units other
than the server. Furthermore, the management device 100 may be
connected in parallel to the two or more projection devices 200,
thus controlling the respective projection devices 200 individually
or integratedly.
Meanwhile, the management device 100 may correct the images
projected by the two or more projection devices 200 and transmit
the corrected images to the respective projection devices 200. In
detail, the management device 100 may individually correct the
images of the respective projection devices 200 based on individual
information of each projection device 200 and transmit the
corrected images to the respective projection devices 200. Here,
the individual information which is taken into account by the
management device 100 during image correction may include a variety
of information such as property information (e.g., the material,
color, reflectivity, shape, installed structure, etc.) of the
projection surface on which each projection device 200 projects an
image, performance information (e.g., the brightness, contrast,
resolution, quality depending on the physical position, etc.) of
each projection device 200, etc., and these information may
preferably be databased and stored in the management device
100.
Moreover, the management device 100 may correct the images based on
information on differences in performance between the projection
devices 200. In detail, the management device 100 may correct the
images of the respective projection devices 200 so as to reduce the
heterogeneity of the images, which may occur due to the differences
in performance, based on the information on the differences in
performance between the two or more projection devices 200 (such as
information on difference in contrast, difference in brightness,
difference in resolution, difference in quality depending on the
physical position).
The image correction based on these differences in performance will
now be described in more detail. First, the management device 100
may reduce the heterogeneity of the images, which may occur due to
a difference in brightness between the respective projection
devices 200, by the image correction. For example, if the
brightness of projection device A is 500 ANSI Lumens, the
brightness of projection device B is 1000 ANSI Lumens, and the
brightness of projection device C is 1500 ANSI Lumens, the
difference in brightness may be offset by the image correction. In
detail, the brightness ratio of the images projected by projection
devices A, B, and C is corrected to 3:2:1, thus offsetting the
heterogeneity of the images which may occur due to the difference
in brightness between the devices. Meanwhile, the image correction
by the difference in brightness may be automatically performed at
every moment when the brightness of each projection device 20
varies, based on the brightness information of the respective
projection devices which are collected in real time. In detail,
each projection device 200 may detect the brightness of the lamp
installed therein and transmit the corresponding information to the
management device 100, and thus the management device 100 can
detect the change in brightness of each projection device 200 based
on the received information. As a result, the management device 100
can newly calculate the difference in brightness upon detection of
the difference in brightness and newly correct the images.
Moreover, the management device 100 may reduce the heterogeneity of
the images, which may occur due to a difference in contrast between
the respective projection devices 200 by the image correction. For
example, if the contrast of projection device A is lower than that
of projection B, the difference in contrast may be offset by
increasing the difference in contrast between pixels of an image
projected by projection A or reducing the difference in contrast
between pixels of an image projected by projection B.
Furthermore, the management device 100 may reduce the heterogeneity
of the images, which may occur due to a difference in resolution
supported by the respective projection devices 200 or a difference
in physical position (e.g., a distance between the projection
surface and the projection device 200), by the image correction. In
detail, the physical positions (e.g., distances to the projection
surface) of the two or more projection devices 200 and the
resolutions supported by the two or more projection devices 200 are
different from each other, and in this case, if the images of the
projection devices 200 are corrected in the same manner, the
qualities of the images reproduced by the respective projection
devices 200 may be different from each other. This is because the
sizes of unit pixels of the images projected on the projection
surface may be different from each other due to the difference in
physical position and a specific projection device 200 may not
support a specific resolution. Therefore, it is preferable that the
management device 100 individually corrects the images of the
respective projection devices 200 based on these differences so as
to reduce the difference in quality of the images by the image
correction. For example, the management device 100 may calculate
information on the sizes of unit pixels of the images, reproduced
by the respective projection devices 200, based on the resolution
supported by each projection device 200 and the physical position
of each projection device 200, and correct the images of the
respective projection devices 200 such that the sizes of unit
pixels are equal to each other in all projection devices 200.
Meanwhile, the management device 100 may manage information related
to maintenance of the two or more projection devices 200 and
transmit the information to the outside or autonomously display the
information thereon. detail, the management device 100 may manage
cumulative operation time information of a lamp or cooling fan
installed in each projection device 200 and inform the replacement
time of the lamp or cooling fan based on this information.
Moreover, the management device 100 may manage brightness
information of the lamp installed in each projection device 200 and
inform a lamp, which needs to be replaced, based on this
information. Furthermore, the management device 100 may manage
information on difference in brightness between lamps installed in
the two or more projection devices 200 and inform the need to
replace a lamp based on this information. In addition, the
management device 100 may manage position information of each
projection device 200 and, if the position of a specific projection
device is changed, inform the corresponding event based on this
information. Additionally, the management device 100 may manage
temperature or humidity information of each projection device 200
and inform the need to prevent or check a failure of each
projection device 200 based on this information.
Next, the operation related to maintenance of the management device
100 will be described in more detail.
First, the management device 100 may manage cumulative operation
time of a lamp or cooling fan installed in each projection device
200 and inform the replacement time of the lamp or cooling fan
based on the managed information. In detail, a current detection
device (sensor) may be installed in the lamp or cooling fan of each
projection device 200 to collect operation information by detecting
the current of the lamp or cooling fan, and the collected operation
information may be transmitted to the management device 100 and
managed. As a result, the management device 100 can calculate
secondary information by analyzing the received information and, in
particular, calculate and manage cumulative use time information of
the lamp or cooling fan of each projection device 200. Here, if the
cumulative operation time of the lamp or cooling fan of each
projection device 200 is greater than a predetermined reference
value (e.g., 2000 hours), the management device 100 may recognize
the corresponding event and inform the need to replace the
corresponding lamp or cooling fan in the event of such an event.
For example, the management device 100 may notify the corresponding
event to a manager computer connected thereto or provide
replacement information through a display unit provided therein.
Here, it is preferable that the replacement information provided by
the management device 100 includes identification information of
the projection device 100 which needs to replace the lamp or
cooling fan.
Next, the management device 100 may manage brightness information
of the lamp installed in each projection device 200 and inform a
lamp, which needs to be replaced, based on this information. In
detail, a brightness detection device (sensor) may be installed in
each projection device 200 to collect brightness information of the
lamp, and the collected information may be transmitted to the
management device 100 and managed. As a result, the management
device 100 can collect the brightness information of the lamp
installed in each projection device 200 and, in particular, collect
information on change in brightness over time. Here, if the
brightness of the lamp installed in each projection device 200 is
less than a reference value or is unstably changed over time, the
management device 100 may recognize the corresponding event and
inform the need to replace the lamp in the event of such an event.
For example, the management device 100 may notify the corresponding
event to a manager computer connected thereto or provide
replacement information through a display unit provided therein.
Here, it is preferable that the replacement information provided by
the management device 100 includes identification information of
the projection device 100 which needs to replace the lamp.
Next, the management device 100 may manage information on
difference in brightness between lamps installed in the two or more
projection devices 200 and inform the need to replace a lamp based
on this information. In detail, the management device 100 may
calculate and manage the information on the difference in
brightness between the lamps based on the collected brightness
information of the lamps. In this case, the management device 100
corrects the images of the respective projection devices 200 so as
to offset the difference in brightness based on the calculated
information on the difference in brightness. However, if the
difference in brightness between the lamps increases, the
heterogeneity of the images cannot be offset even by the image
correction. Accordingly, if the difference in brightness between
the lamps is beyond the limit that can be offset by the correction,
the management device 100 may identify the lamp of the projection
device 200, which causes the corresponding difference in
brightness, and inform the need to replace the identified lamp. For
example, the management device 100 may notify the corresponding
event to a manager computer connected thereto or provide
replacement information through a display unit provided therein.
Here, it is preferable that the replacement information provided by
the management device 100 includes identification information of
the projection device 100 which needs to replace the lamp.
Next, the management device 100 may manage position information of
each projection device 200 and if the position of a specific
projection device is unexpectedly changed (e.g., due to an external
environment factor such as vibration), inform the corresponding
event based on the managed information. In detail, a position
detection sensor (e.g., a 3-axis acceleration sensor, 3-axis gyro
sensor, etc.) may be installed in each projection device 200 to
collect the position information by detecting the position of the
projection device, and the collected position information may be
transmitted to the management device 100 and managed. Here, if the
position of each projection device 200 is changed, the management
device 100 may recognize the corresponding event and inform the
change in the position of the projection device in the event of
such an event. For example, the management device 100 may notify
the corresponding event to a manager computer connected thereto or
inform the change in the position through a display unit provided
therein. Here it is preferable that the information provided by the
management device 100 includes identification information of the
projection device 100 whose position is changed.
Next, the management device 100 may manage temperature or humidity
information of each projection device 200 and inform the need to
prevent or check a failure of each projection device 200 based on
this information. In detail, a temperature detection device
(sensor) or humidity detection device (sensor) may be installed in
each projection device 200 to collect temperature or humidity
information of the inside of the projection device 200, and the
collected temperature or humidity information may be transmitted to
the management device 100 and managed. Here, if the temperature of
the inside of a specific projection device 200 is greater than a
reference value (e.g., 80.degree. C.) or if the humidity of the
inside is greater than a reference value (e.g., 80%), the
management device 100 may remotely stop the operation of the
corresponding projection device 200. Moreover, the management
device 100 may provide information for requesting to check the
corresponding projection device 200 together with its
identification information.
Meanwhile, the two or more projection devices 200 may project
images on a plurality of projection surfaces which are arranged not
to be parallel to each other. Moreover, the two or more projection
devices 200 may project images, which are synchronized with each
other, on the plurality of projection surfaces. Here, it is
preferable that a unified image is reproduced on the entire
projection surface, and separate images may be reproduced on the
plurality of projection devices depending on the situations.
Here, the plurality of projection surfaces may be arranged so as
not to be parallel to each other. According to the prior art, an
image is projected only on a screen placed in front of a theater
such that an audience watches the image reproduced on the
two-dimensional screen or a 3D technology is applied to the image
itself reproduced on a plane. On the contrary, according to the
present invention, the plurality of projection surfaces are
three-dimensionally arranged so as not to be parallel to each
other, and thus it is possible to provide the audience with a
three-dimensional image with high 3D effect and involvement through
the three-dimensionally arranged plurality of projection surfaces
without applying the 3D technology to the image itself.
Moreover, it is preferable that the plurality of projection
surfaces are arranged to surround an auditorium in the theater.
Therefore, the audiences can feel as if they are in a space created
by the unified image reproduced on the plurality of projection
surfaces, and thus the three-dimensional effect, involvement, and
virtual reality that the audiences feel can be maximized.
Furthermore, the angle between the plurality of projection surfaces
is not limited to a specific angle, and the plurality of projection
surfaces may be arranged at various angles as long as the audiences
can feel the three-dimensional effect.
In addition, the plurality of projection surfaces may be arranged
to be adjacent to each other or to be spaced from each other and,
even in this case, it is preferable that the plurality of
projection surfaces are arranged to surround the auditorium.
FIG. 3 is a diagram showing an example in which the plurality of
projection surfaces are arranged on the front, left, and right
sides with respect to the auditorium, FIG. 4 is a diagram showing
an example in which the plurality of projection surfaces are
arranged on the front, left, right, and top sides with respect to
the auditorium, and FIG. 5 is a diagram showing an example in which
the plurality of projection surfaces are arranged on the front,
left, right, top, and bottom sides with respect to the
auditorium.
Meanwhile, the plurality of projection surfaces may comprise
different types of projection surfaces. For example, the plurality
of projection surfaces may be configured in such a manner that a
screen and a wall are mixed, different types of screens are mixed,
or different types of walls are mixed. Thus, the present invention
is also applicable to a conventional theater comprising a single
screen and a plurality of walls and can implement a
multi-projection service even though a plurality of screens are not
provided. However, in these environments, the unity of the images
reproduced on the plurality of projection surfaces may be reduced
due to heterogeneity (color, reflectivity, etc.) between the screen
and the walls, but this problem can be overcome by image correction
of the management device 100. In detail, the management device 100
may individually correct the images projected on the respective
projection surfaces based on the relative properties (color,
reflectivity, etc.) of the screen and the walls, thus creating a
unified image on the entire projection surface.
Moreover, the number of projection devices 200 which project images
on the respective projection surfaces may differ depending on the
size of each projection surface. For example, two or more
projection devices 200 may project images together on a projection
surface of a relatively large size, and a single projection device
200 may project an image on a projection surface of a relatively
small size. Meanwhile, in the case where two or more projection
devices project images on a single projection surface, the
overlapping parts of the images projected by the respective
projection device 200 may not be smooth, which can be solved by
edge blending correction of the management device 100.
Meanwhile, the management device 100 may preferably perform image
correction (first correction) based on the differences in
performance of the projection devices 200 and image correction
(second correction) based on the properties of the plurality of
projection surfaces at the same time. Through the two-phase image
correction (first and second corrections), the unity of the images
projected on the plurality of projection surfaces can be further
increased.
The first correction is based on the differences in performance of
the projection devices 200, which has been described in detail
above.
The second correction is based on the properties of the plurality
of projection surfaces and may be performed by the management
device 100. Here, the properties of the projection surfaces may
include various properties related to the projection surfaces, such
as the material, color, reflectivity, shape of the projection
surface, installed structure, etc.
The second correction will now be described in more detail. The
management device 100 may correct the images projected by the two
or more projection devices 200 based on the properties of the
plurality of projection surfaces. In detail, the management device
100 may correct the images by individually or relatively analyzing
the shape, material, color, reflectivity, brightness, etc. of the
plurality of projection surfaces such that the two or more
projection devices 200 can create a unified image. For example, the
management device 100 may correct the images by analyzing the
differences in color, reflectivity, brightness, etc. of the
respective projection surfaces so as to offset the analyzed
differences. Moreover, the management device 100 may perform image
warping correction, masking correction, etc. based on the shapes of
the respective projection surfaces so as to prevent image
distortion on each projection surface. Furthermore, the management
device 100 may increase the unity of images by edge blending
correction based on the shapes of the respective surfaces.
Various embodiments for ensuring the unity of the images projected
by the two or more projection devices 200 have been described. In
detail, the image correction (1) based the differences in
performance of the respective projection devices 200 and the image
correction (2) based on both the differences in performance of the
respective projection devices 200 and the properties of the
projection surfaces have been described.
Meanwhile, the management device 100 may ensure the unity of images
by another embodiment, which will be described in brief below.
According to another embodiment of the present invention, the
management device 100 may ensure the unity of images in a manner to
equally maintain output values of lamps included in the respective
projection devices 200 after the above-described image correction
based on the properties of the projection surfaces (if the output
values of the lamps are different from each other, the
heterogeneity of images may occur). That is, the management device
100 can ensure the unity of images in a manner to perform the
correction based on the properties of the plurality of projection
surfaces and then control the output values of the lamps of the
respective projection devices 200.
Here, the output value (brightness) of the lamp included in each
projection device 200 may preferably be changed by electronic
control or controlled by the management device 100. Moreover, the
management device 100 may detect in real time the output value of
the lamp by means of a sensor device included in each projection
device 200. Thus, the management device 100 can integratedly manage
the output values of the lamps included in the two or more
projection devices 200 and, when the output value of a lamp
included in a specific projection device is changed, can change the
output value to be the same as others by means of a control
signal.
Meanwhile, the correction based on the properties of the plurality
of projection surfaces is the same as the above-described second
correction, and thus detailed description thereof will be
omitted.
That is, each projection device 200 receives an image, which is
corrected based on the properties of the projection surface (e.g.,
the shape, material, color, reflectivity, brightness, etc.), from
the management device 100 and projects the corrected image on the
corresponding projection surface. Here, if the performances of the
respective projection devices 200 (e.g., the output values of the
lamps) are different from each other, the sense of color or unity
between the images may be somewhat reduced. Therefore, when the
management device 100 equally controls the states of all projection
devices 200 in the theater (e.g., the output values (definition,
etc) of the lamp), the above problem can be solved, thus outputting
unified images with unified color.
Meanwhile, it is apparent that the management device 100 can change
the projection angle, installation position, etc. of each
projection device 200 based on an external input signal so as to
precisely match the positions of the images projected on the
plurality of projection surfaces. Here, the projection angle of
each projection device 200 may preferably be changed by electronic
control or controlled by the management device 100. Likewise, the
installation position of each projection device 200 may preferably
be changed by electronic control (e.g., rails are provided on the
installation surface of the projection device to move to a
corresponding coordinate value) or controlled by the management
device 100.
Next, the maintenance operation performed by a projection device
management system in accordance with an embodiment of the present
invention will be described with reference to FIGS. 6 to 8.
Referring to FIG. 7, the management device 100 may comprise an
image correction unit 110, a maintenance management unit 120, a
temperature management unit 130, a humidity management unit 140, a
display unit 150, a storage unit 160, and a control unit 170.
The image correction unit 110 corrects the images projected by the
two or more projection devices 200. It is preferable that the image
correction unit 110 individually performs the image correction for
each projection device 200 and, in particular, differentially
corrects the images of the respective projection devices 200 based
on the difference in brightness between the respective projection
devices 200.
The maintenance management unit 120 generally manages information
related to the maintenance of the two or more projection devices
200 and processes or provides a variety of information related to
the maintenance. For example, the maintenance management unit 120
may inform the replacement time of a lamp or cooling fan installed
in each projection device 200 by calculating cumulative operation
time information of the lamp or cooling fan or determine the need
to replace the lamp by analyzing brightness information of the lamp
installed in each projection device 200. Moreover, the maintenance
management unit 120 may determine the need to replace the lamp by
recognizing information on the difference in brightness between the
projection devices 200. Furthermore, the maintenance management
unit 120 may manage position information of each projection device
200 and identify an unexpected change in position of a specific
projection device.
The temperature management unit 130 and the humidity management
unit 140 manage the temperature and humidity of the inside of the
projection device 200. The temperature management unit 130 and the
humidity management unit 140 may inform the need to prevent or
check a failure of each projection device 200 by analyzing
temperature and humidity information of the projection device 200.
For example, if the internal temperature or humidity of a specific
projection device 200 is greater than a reference value, the
temperature management unit 130 or the humidity management unit 140
may remotely stop the operation of the corresponding projection
device 200 and inform the need to check the corresponding
projection device 200.
The display unit 150, which may be further optionally included in
the management device 100, displays a variety of information
managed by the management device 100. The above-described
information related to the maintenance may be displayed on the
display unit 150 and, in this case, it is preferable that
information related to the maintenance includes identification
information of a projection device 200 having a failure. Meanwhile,
the display unit 150 may be integrally included in the management
device 100, may be configured as a separate external connection
device, or may be implemented with various display devices.
The storage unit 160 stores a variety of information related to the
operation of the management device 100. The storage unit 160 may
temporarily or permanently store the above-described information
related to the maintenance.
The control unit 170 controls various operations of the management
device 100 including the operations of the image correction unit
110, the maintenance management unit 120, the temperature
management unit 130, the humidity management unit 140, and the
display unit 150. The control unit 170 may be implemented in
various arithmetic units.
Referring to FIG. 8, each projection device 200 may comprise an
image projection unit 210, a current detection unit 220, a
brightness detection unit 230, a temperature detection unit 240, a
humidity detection unit 250, and a position detection unit 260.
The image projection unit 210 projects a corrected image
transmitted from the management device 100 on a projection surface.
The image projection unit 210 may receive the corrected image from
the management device 100 and project the received image on the
projection surface and, in this case, the corresponding image has
been corrected based on the properties of the projection surface
(e.g., the brightness, material, color, reflectivity, shape,
installed structure, etc.) and the performance of the projection
device (e.g., the brightness, contrast, resolution, etc.).
Meanwhile, a lamp may be included in the image projection unit 210,
and the brightness of the projected image can be adjusted by the
lamp.
The current detection unit 220 detects the operation (on) of a
cooling fan or lamp installed in the projection device 200. In
detail, the current detection unit 220 may determine whether the
cooling fan or lamp operates (on) by detecting the current flowing
in the cooling fan or lamp and transmit the detected information to
the management device 100.
The brightness detection unit 230 detects the brightness of the
lamp that may be included in the image projection unit 210 and
transmits the detection brightness information to the management
device 100. The brightness detection unit 230 may be implemented
with various sensor devices.
The temperature detection unit 240 and the humidity detection unit
250 detect the temperature and humidity of the inside of the
projection device 200 and transmit the detected temperature and
humidity information to the management device 100. The temperature
detection unit 240 and the humidity detection unit 250 may be
implemented with various sensor devices.
The position detection unit 260 detects the position of the
projection device 200 and transmits the detected position
information to the management device 100. The position detection
unit 260 may be implemented with various sensor devices for
detecting the position, such as a 3-axis acceleration sensor,
3-axis gyro sensor, etc.
The maintenance operation performed by the projection device
management system will now be described with reference to FIGS. 6
to 8. The maintenance operation of the projection device management
system may be generally divided into five operations. In detail,
the maintenance operation of the projection device management
system may be divided into (1) maintenance operation based on the
operation time of a lamp or cooling fan installed in each
projection device 200, (2) maintenance operation based on
brightness information of the lamp installed in each projection
device 200, (3) maintenance operation based on information on
difference in brightness between the lamps installed in two or more
projection devices 200, (4) maintenance operation based on position
information of each projection device 200, and (5) maintenance
operation based on temperature or humidity information of each
projection device 200.
Firstly, the maintenance operation based on the operation time of
the lamp or cooling fan installed in each projection device 200
will now be described. The current detection unit 220 of each
projection device 200 collects operation information (on) of the
lamp or cooling fan of each projection device 200 by detecting the
current flowing in the lamp or cooling fan of the projection device
200. The operation information collected by the current detection
unit 220 of each projection device 200 is transmitted to the
maintenance management unit 120 of the management device 100, and
thus the maintenance management unit 120 calculates cumulative
operation time information of the lamp or cooling fan based on the
collected information and manage each projection device 200 based
on the collected information. Meanwhile, if the cumulative
operation time of a specific lamp or cooling fan is greater than a
predetermined reference value (e.g., 2000 hours), the maintenance
management unit 120 may recognize the corresponding event and
inform the need to replace the lamp or cooling fan in connection
with the display unit 150 in the event of such an event. Here, it
is preferable that the information for informing the need to
replace the lamp or cooling fan includes identification information
of the projection device 200 which needs to replace the lamp or
cooling fan. Moreover, the maintenance management unit 120 may
calculate in real time the cumulative operation time of the lamp or
cooling fan of each projection device 200 and provide the
calculated cumulative operation time through the display unit 150
in real time or at regular intervals (e.g., at a cumulative
operation time of 500 hours, 1000 hours, 1500 hours, or 2000
hours).
Meanwhile, while the foregoing has described that the projection
device 200 is informed about the replacement time of the
corresponding lamp or cooling fan by the management device 100, the
projection device 200 may determine the replacement time of the
corresponding lamp or cooling fan based on the operation
information collected by the current detection unit 220 and
autonomously issue a warning (e.g., using a display unit, speaker,
etc. included in the projection device).
Secondly, the maintenance operation based on the brightness
information of the lamp installed in each projection device 200
will now be described. The brightness detection unit 230 of each
projection device 200 collects the brightness information of the
lamp installed in each projection device 200 and, in particular,
collects information on change in brightness over time. The
information collected by the brightness detection unit 230 of each
projection device 200 is transmitted to the maintenance management
unit 120 of the management device 100, and thus the maintenance
management unit 120 diagnoses the performance of the lamp installed
in each projection device 200 based on the collected information.
In detail, if the brightness of a specific lamp installed in each
projection device 200 is less than a reference value or is unstably
changed over time, the maintenance management unit 120 may
recognize the corresponding event and inform the need to replace
the lamp through the display unit 150 in the event of such an
event. Here, it is preferable that the information for informing
the need to replace the lamp includes identification information of
the projection device 200 which needs to replace the lamp.
Moreover, the maintenance management unit 120 may provide the
brightness information of the lamp installed in each projection
device 200 through the display unit 150 in real time.
Meanwhile, if it is determined based on the brightness information
collected by the brightness detection unit 230 that the brightness
is less than a reference value or is unstably changed, the
projection device 200 may determine that there is a failure and
issue a warning (e.g., using a display unit, speaker, etc. included
in the projection device) autonomously.
Thirdly, the maintenance operation based on the information on the
difference in brightness between the lamps installed in the
projection devices 200 will now be described. The maintenance
management unit 120 may calculate and manage the information on the
difference in brightness between the lamps, installed in the two or
more projection devices 200, based on the collected brightness
information of the lamps. Here, the image correction unit 110 may
correct the images of the respective projection devices 200 so as
to offset the difference in brightness between these lamps based on
the calculated information on the difference in brightness.
However, if the difference in brightness between the lamps
increases, the heterogeneity of the images cannot be offset even by
the image correction. Accordingly, the maintenance management unit
120 may recognize the case where the difference in brightness
between the lamps is beyond the limit that can be offset by the
correction (where the difference in brightness is greater than a
reference value), identify the lamp of the projection device 200,
which causes the corresponding difference in brightness, and inform
the need to replace the identified lamp. Here, it is preferable
that the information for informing the need to replace the lamp
includes identification information of the projection device 200
which needs to replace the lamp. Moreover, the maintenance
management unit 120 may provide the information on the difference
in brightness between projection devices 200 through the display
unit 150 in real time.
Fourthly, the maintenance operation based on the position
information of each projection device 200 will now be described.
The position detection unit 260 of each projection device 200
collects the position information of each projection device 200,
and the collected information is transmitted to the maintenance
management unit 120 of the management device 100. Here, the
maintenance management unit 120 determines whether the position of
each projection device 200 is changed based on the collected
information and, in particular, determines whether the
three-dimensional position of each projection device is changed. As
a result of the determination, if the position of a specific
projection device is changed, the maintenance management unit 120
may inform the corresponding event through the display unit 150.
Here, it is preferable that the information for informing the
change in the position of the specific projection device 200
includes identification information of the specific projection
device 200 whose position is changed.
Meanwhile, the maintenance management unit 120 may directly correct
the position of the specific projection device, whose position is
changed, by electronic control. In this case, the position of each
projection device 200 may preferably be changed by electronic
control (e.g., rails are provided on the installation surface of
the projection device to move to a corresponding coordinate
value).
Moreover, if it is determined based on the position information
collected by the position detection unit 260 that the position is
changed, the projection device 200 may inform the change in the
position and autonomously issue a warning (e.g., using a display
unit, speaker, etc. included in the projection device).
Fifthly, the maintenance operation based on the temperature or
humidity information of each projection device 200 will now be
described. The temperature detection unit 240 or the humidity
detection unit 250 of each projection device 200 detects the
temperature or humidity of the inside of each projection device 200
and collects relevant information. The information collected by the
temperature detection unit 240 or the humidity detection unit 250
of each projection device 200 is transmitted to the temperature
management unit 130 or the humidity management unit 140 of the
management device 100, and thus the temperature management unit 130
or the humidity management unit 140 may inform the need to prevent
or check a failure of each projection device 200 by analyzing the
received temperature or humidity information. In detail, if the
temperature of the inside of a specific projection device 200 is
greater than a reference value (e.g., 80.degree. C.) or if the
humidity of the inside is greater than a reference value (e.g.,
80%), the temperature management unit 130 or the humidity
management unit 140 may remotely stop the operation of the
corresponding projection device 200. Moreover, the temperature
management unit 130 or the humidity management unit 140 may provide
information for requesting to check the corresponding projection
device 200 together with its identification information through the
display unit 150.
Meanwhile, if it is determined based on the temperature or humidity
information collected by the temperature detection unit 240 or the
humidity detection unit 250 that the temperature or humidity is
greater than a reference value, the projection device 200 may
determine that there is a failure and autonomously issue a warning
(e.g., using a display unit, speaker, etc. included in the
projection device).
As described above, according to the present invention, even when
two or more projection devices are installed in a theater, it
possible to integratedly manage and control the projection
devices.
Moreover, the present invention can individually correct images
projected by the respective projection devices based on differences
in performance between the respective projection devices. In
detail, the present invention can recognize information on the
differences in performance between the respective projection
devices (e.g., a difference in contrast, difference in resolution,
difference in brightness or quality due to a difference in physical
position, etc.) and correct the images projected by the respective
projection devices so as to reduce these differences.
Furthermore, the present invention can manage operation time
information based on the current input to a lamp or cooling fan and
inform the replacement time of the lamp or cooling fan based on the
managed operation time information. Thus, since the replacement
time of the lamp is determined based on the operation state of the
lamp, it is possible to inform the replacement time more accurately
than a conventional method of informing the replacement time based
only on the use time. According to the conventional method based on
the use time, the replacement time is calculated without
considering the operation time of the lamp while the shutter is
closed, and thus it is impossible to provide accurate
information.
In addition, the present invention can recognize the brightness of
the lamp by means of a sensor and inform the need to replace the
lamp even when there is a problem in the brightness of the lamp. In
detail, if the brightness of the lamp is low or the change in
brightness over time is large even if the lamp is not used for a
long time, it is possible to detect the fact and inform the need to
replace the lamp. Thus, it is possible to detect the occurrence of
a problem in the lamp, which cannot be detected by checking the
operation time only, thus making it possible for the projection
device to project a high-quality image.
Additionally, the present invention can compare the brightness of
the lamps installed in the two or more projection devices and, if
the difference in brightness between the lamps is greater than a
predetermined value, inform the need to replace the lamp. In
detail, if the difference in brightness between the lamps is beyond
the limit that can be offset by the correction, it is possible to
direct the replacement of the corresponding lamps, thus preventing
the respective projection devices from projecting heterogeneous
images.
Moreover, the present invention can detect the temperature and
humidity of each projection device and, if the temperature or
humidity of a specific projection device is greater than a
predetermined value, remotely stop the operation of the
corresponding projection device. Thus, it is possible to prevent
the projection devices from operating in high-temperature and
high-humidity environment, which may cause a failure of the device,
thus preventing the failure of the device and increasing the
durability.
Furthermore, the present invention can provide an audience with an
image with high 3D effect and involvement by projecting images on a
plurality of projection surfaces.
In addition, the present invention can provide the audience with a
multi-viewpoint image by projecting synchronized images on the
plurality of projection surfaces that surround an auditorium, thus
allowing the audience to experience a sense of reality as if he or
she actually exists in a space depicted in the image.
Additionally, according to the present invention, the two or more
projection devices, which project images on the plurality of
projection surfaces, are integratedly managed and synchronized by a
management device, and thus a synchronized and unified image can be
reproduced on the entire projection surface.
Moreover, the present invention can effectively manage the lamps or
cooling fans included in two or more projection devices. In detail,
when two or more projection devices are installed in a single
theater, the replacement times of the lamps or cooling fans
included in the two or more projection devices are different, which
makes it difficult to manage. However, the present invention can
inform the replacement times of these lamps or cooling fans in
advance, thus resolving the difficulty in management.
Furthermore, the present invention can perform both the image
correction based on the performances of the projection devices and
the image correction based on the properties of the projection
surfaces at the same time. Thus, it is possible to further increase
the unity of images projected on the plurality of projection
surfaces by the two-phase image correction.
In addition, the present invention can detect an involuntary change
in position of each projection device and, if the involuntary
change in position is detected, inform the change in the position
or return it to its original position by remote control. Thus, even
if the position of each projection device is unexpectedly changed
by a change in environment of the theater, it is possible to inform
or correct the change, thus preventing deterioration of image
quality due to the change in the position of the projection
device.
While the invention has been shown and described with reference to
certain preferred embodiments thereof, it will be understood by
those skilled in the art that various changes in form and details
may be made therein without departing from the spirit and scope of
the invention as defined by the appended claims. Therefore, the
scope of the invention is defined not by the detailed description
of the invention but by the appended claims, and all differences
within the scope will be construed as being included in the present
invention.
* * * * *